Fracturing of subterranean geological structures can be useful for assisting in the development of hydrocarbon resources from subterranean reservoirs. More particularly, in certain types of formations, fracturing of a region surrounding a well or borehole can allow for improved flow of oil and gas. A conventional method for causing such fracturing in the geologic structure involves generating hydraulic pressure, which may be a static or quasi-static pressure generated in a fluid in the borehole. Another conventional method includes generation of a shock in conjunction with a hydraulic wave by creating an electrical discharge across a spark gap. U.S. Pat. No. 8,220,537, titled “Pulse fracturing device and method,” describes a fracture method that includes generating an acoustic wave in a fluid medium present in the borehole.
While conventional methods have been used successfully to form fractures, there is a continued need for an improved method and apparatus for generating high-pressure pulses in a subterranean medium and causing fracturing to occur.